Detergent cup trip mechanism



Nov. 6, 1962 D. s. CUSHING DETERGENT cu TRIP MECHANISM Filed May 25, 1960 9 f 7 /I.. v 6 A, fifw x INVENTOR.

DONALD S. CUSHING Wfm l A A r 5? n 8 4||ll m w LP M, 4 s M 4 Z Z iz F JJ I .llll hnul uhflmhl l hl hmlmwmmu mm. M L? [a 3 .I... e o m z I 1 l z 1 4 m G u 1 4/ m E E. H r. u m

H IS ATTORNEY Patented Nov. 6, 1962 3,062,412 DETERGENT CUP TRIP MECHANISM Donald S. Cushing, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed May 25, 1960, Ser. No. 31,760 6 Claims. (Cl. 222-166) The present invention relates to a dispensing mechanism and particularly to a low cost timer controlled mechanism for dispensing detergents into an automatic dishwasher tub.

It is not new to provide a timer controlled detergent cup for an automatic dishwasher. However, the known types of detergent dispensers have been relatively complicated mechanical devices or magnetically supporting and tripping mechanisms for the detergent cup. The present invention is a simplification of a timer controlled detergent dispenser that is both fool-proof in operation and reliable over a long period of time.

The principal object of this invention is to provide a cam operated dispenser where the cam serves to support the cup of the dispenser in the upright fill position.

A further object of the present invention is to provide a trip mechanism for a dispenser where the mechanism may be included within the casing of a standard electric timer for appliances and the like.

A further object of the present invention is to design a cam track and cam follower as the supporting and tripping mechanism for a detergent dispenser.

The preferred embodiment of the present invention incorporates a detergent cup that is supported upon a rotatable shaft. The shaft is normally biased by a spring member to dump the cup. The shaft is adapted to rotate through an angle whereby the cup will either be supported in an upright fill position or an inverted dump position. The dispenser is designed to be actuated by a timer mechanism such as an appliance timer of the electrical type.

Positioned between the timer and the shaft of the detergent cup is a cam track and cam follower where the cam track is provided with a drop-off position and a reset position. Spring means cooperate with the shaft so that the spring is loaded when the cup is in the upright fill position. The cup is emptied automatically by the turning force of the spring when the cam follower reaches the drop-01f position of the cam track. The cup i automatically returned to its upright fill position when the cam follower reaches the reset position of the cam track. The cam track is so designed that the detergent cup is supported in its upright fill position by the cooperation of the cam follower and the cam track so that there are a minimum number of simple elements that are combined to make up this design.

My invention will be better understood from the following description taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

FIGURE 1 is a crosssectional side elevational view taken through a portion of the wall of a dishwasher tub showing a detergent cup at the left within the tub and a cooperating timer mechanism at the right supported on the outer surface of the tub;

FIGURE 2 is a cross-sectional elevational view showing the nature of the cam member of the timer mechanism and the cam follower taken on the lines 22 of FIGURE 1;

FIGURE 3 is a cross-sectional view similar to that of FIGURE 2 showing the cam member after it has rotated counter-clockwise so that the cam follower has ridden off of the drop-off position of the cam track to dump the detergent cup;

FIGURE 4 is a cross-sectional side elevational view similar to that of FIGURE 1 showing the cup in the inverted position.

Referring in detail to the drawing and in particular to FIGURE 1, 10 shows a cross-sectional view of a portion of a vertical wall of a dishwasher tub. On the inner side of the tub wall 10 is a detergent cup 11 having a pivoted top cover 12, while a. timer mechanism 13 is positioned on the outer surface of the tub wall 10. A shaft 14 supports the cup 11 and extends through the wall 10 for cooperation with a cam member 15 of the timer mechanism 13. As is best seen in FIGURES 1 and 2, the outermost end of the shaft 14 supports a lever arm 16 and a cam follower 17 in the form of a pin member for riding on a cam track 1% of the cam member 15. The other side of the cam 15 has a plurality of cam tracks (not shown) to provide the necessary electrical sequencing of events in cooperation with a plurality of spring contact blades (not shown) as in standard timer constructions.

The cover 12 is pivoted along the back side of the cup 11 by fixed trunnions 19 of the cup fitted through enlarged openings 19a of the cover as is best seen in FIGURE 4. Hence, when the cup 11 is inverted the cover will fall open by the action of gravity as well as a centrifugal force. The cup 11 is of molded plastic material and it has a D-shaped opening 20 that extends through its bottom wall for receiving a mating portion of the shaft 14 so that the cup may not turn with respect to the shaft. A metal plate 21 reinforces the connection between shaft 14 and the cup 11 by sliding in opposed grooves 22 in the back side of the cup and being locked in place by receiving a portion of the D-shaped shaft 14 as is best seen in FIGURE 1. A snap ring or similar fastener 22a is fitted on the innermost end of the shaft 14 to prevent the cup from being removed therefrom.

The outermost end of the shaft 14 is provided with an enlarged head 23 that is made integral with the lever arm 16 of the cam follower 17. Positioned behind the cam lever 16 is a torsion spring 24 that is fastened at one end to the shaft 14, its other end 24a is confined against a projection 25 as seen in FIGURE 2. This projection 25 is an integral part of a mounting plate 26 that is fastened by screw means 27 to the tub wall 10. This mounting plate 26 includes a bushing 28, as seen in FIGURE 1, that is swaged in an opening in the mounting plate and extends through a suitable opening in the tub wall 10. A suitable metal washer 29 and a resilient washer 30 are fitted over the bushing on the innermost side thereof, and a clamping nut 31 is threaded onto the bushing for sealing the bushing in the tub wall 10. The shaft 14 extends through the center of the bushing and a rubber O-ring 32 is positioned to engage the shaft and prevent moisture from leaking through the bearing of the bushing. A spring clip 33 straddles the shaft to hold the O-ring in place.

The timer mechanism 13 includes a "standard clock motor 35 driving a gear train 36 which meshes with external gear teeth 37 on the periphery of the cam member 15. The previously mentioned cam track 18 of the cam member 15 is best illustrated in FIGURES 2 and 3. It is shown as an irregular inside surface adjacent the periphery of the cam although it should be recognized that an irregular outside surface adjacent the center portion of the cam will operate almost equally as well. In both events the cam track 18 has a wearing surface that is parallel to the pivotal axis of the cam member 15 as well as the pivotal axis of the shaft 14 of the detergent cup 11. Such a design has many advantages of space, simplicity, and ease of manufacture.

Cam track 18 may be described as having five segments namely, a reset position 39, an idler position 40, a dropoif position 41, a turnaround area 42 which allows the cam follower 17 to turn in a clockwise direction for inverting the detergent cup, and an inactive portion 43, at which time the cup will remain inverted during the washing and later rinsing cycles. During the latter part of the drying portion of the cycle, the cam follower 17 will be engaged by the reset surface 39 of the cam track 18 thereby reloading the torsion spring 24 and returning the detergent cup 11 to its upright fill position as the cam member continues to turn. Accordingly, the detergent cup will always be in the upright fill position after the washing operation is completed. Once the ma chine is started the cam member 15 will begin to rotate but the cam follower is not tripped since it is moving on the circular idler portion 40 of the track between the reset position 39 and the drop-off position 41. It is during this time that the tub is first drained of all water and a preliminary rinse cycle is accomplished. At the precise time for dispensing the detergent the cam follower will ride off the drop-off position 4-1 so that the cam follower is free to swing under the bias of the torsion spring 24. The spring causes the lever arm 16 to turn through an angle of about 130 until its motion is halted by striking a stop 44 on the mounting plate 26 as is best seen in FIGURE 3. Notice the cover 12 in FIGURE 3 hanging down in the open position thereby allowing the detergent to spill into the tub.

Having described above a novel trip mechanism for a dispenser it will be readily apparent to those skilled in this art that I have devised an efficient mechanism for both supporting, dumping, and resetting the detergent cup automatically during a washing operation. I have likewise incorporated the cam track on one side of the cam member of a standard timer device used in appliances so that improved results and greater reliability have resulted from the introduction of this design on the market. While this invention has been illustrated as a trip mechanism for the entire cup it should be recognized that the same mechanism could actuate a trap door in the cup or a movable side cover plate for dispensing the contents of the cup.

Modifications of this invention will occur to those skilled in this art and it is to be understood, therefore, that this invention is not limited to the particular embodiments disclosed but that it is intended to cover all modifications which are within the true spirit and scope of this invention as claimed.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A dispenser comprising a cup that is mounted on one end of a shaft, the shaft being supported to rotate through an angle that will empty the contents of the cup, the other end of the shaft supporting a cam follower, a motor driven timer mechanism having a cam member for cooperation with said cam follower, said cam member having a track with a drop-off position and a reset position, and spring means cooperating with the shaft and normally biasing the shaft to overturn the cup so that the spring is loaded when the cup is in the upright fill position, whereby the cup is emptied suddenly by the force of the spring means when the cam follower rides off the drop-off position of the cam track, and the springs means is reloaded and the cup is returned automatically to its upright fill position when the cam follower rides upon the reset position of the cam track.

2. A dispenser comprising a cup that is fixed to a shaft, the shaft being rotatably supported so that the cup has an upright fill position and an inverted dump position which will empty the contents of the cup, a cam follower mounted on the shaft, a motor driven timer mechanism having a cam member for cooperation with said cam follower, said cam member having a track with a dropoff position and a reset position, and spring means cooperating with the shaft and normally biasing the shaft to overturn the cup so that the spring is loaded when the cup is in the upright fill position, whereby the cup is emptied by the force of the spring means when the cam follower rides off the drop-off position of the cam track, and the spring means is reloaded and the cup is returned to its upright fill position when the cam follower rides upon the reset position of the cam track.

3. A dispenser comprising a cup that is fastened to a shaft, the shaft being supported to rotate from an upright fill position of the cup to an inverted dump position that will empty the contents of the cup, a timer mechanism cooperating with the shaft of the cup, there being a cam track and cam follower combination positioned between the timer mechanism and the shaft, the cam track including a drop-off position and a reset position, and spring means cooperating with the shaft and normally biasing the shaft to overturn the cup so that the spring is loaded when the cup is in the upright fill position, whereby the cup is emptied by the releasing force of the spring when the cam follower rides ofi the dropoff position of the cam track, and the spring means is reloaded and the cup is returned to its upright fill position when the cam follower rides upon the reset position of the cam track.

4. A detergent dispenser comprising a cup that is mounted on one end of a shaft, the shaft being rotatably supported in an opening in a supporting wall and being capable of rotating through an angle greater than the other end of the shaft including a cam follower, a torsion spring, and a mounting plate, the mounting plate serving to fasten the shaft to the supporting wall, the torsion spring acting upon the shaft and being loaded when the cup is in the upright fill position thereby normally biasing the shaft to overturn the cup, a timer mechanism having a motor driven cam member cooperating with the cam follower, said cam member having a track with a drop-off position so that at a predetermined time the cam follower will be released thereby freeing the torsion spring to drive the detergent cup to its inverted position.

5. A detergent cup as recited in claim 4 wherein the cam track has a reset position which engages the follower and reloads the spring means so that the cup is automatically returned to its upright fill position.

6. A dispenser comprising a cup and means for emptying the contents of the cup comprising a cam follower cooperating with a cam member of a timer mechanism, said cam member having a track with a drop-off position and a reset position, and spring means cooperating with the shaft and normally biasing the shaft to overturn the cup so that the spring is loaded when the cup is in the upright fill position, whereby the cup is emptied by the force of the spring means when the cam follower rides off the drop-off position of the cam track, and the spring means is reloaded and the cup is returned to its upright fil'l position when the cam follower rides upon the reset position of the cam track.

References Cited in the file of this patent UNITED STATES PATENTS 

